What is Bose-einstein: Definition and 79 Discussions

In condensed matter physics, a Bose–Einstein condensate (BEC) is a state of matter (also called the fifth state of matter) which is typically formed when a gas of bosons at low densities is cooled to temperatures very close to absolute zero (−273.15 °C or −459.67 °F). Under such conditions, a large fraction of bosons occupy the lowest quantum state, at which point microscopic quantum mechanical phenomena, particularly wavefunction interference, become apparent macroscopically. A BEC is formed by cooling a gas of extremely low density (about one-hundred-thousandth (1/100,000) the density of normal air) to ultra-low temperatures.
This state was first predicted, generally, in 1924–1925 by Albert Einstein following and crediting a pioneering paper by Satyendra Nath Bose on the new field now known as quantum statistics.

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  1. bbbl67

    I What happens to the electrons in a Bose-Einstein Condensate?

    When various atoms are turned into BEC's, are their electrons still arranged in their standard atomic orbitals like at higher temperatures? Or are the electrons free floating around the entire condensate? If the electrons are free-floating, then are they arranging themselves into superconductive...
  2. T

    I Bose-Einstein numerical integration

    Want to integrate the total energy density over all photon energies between two temperature values from 500K to 5800K, but not sure how to proceed. Here is some examples to help:
  3. iymasomhumaan

    B Nuclear wavefunction and Bose-Einstein condensates

    Einstein condensate state or ultra hot fully ionized, removed of all-electron, plasma that is compressed like possibly something like fusion, state (an extraordinarily unattainable state currently; like compressed air into a liquid, but a solid; while even metallic hydrogen is, as far as I know...
  4. J

    I Bose-Einstein condensate diagram

    I have seen many of these diagrams in internet and I fail to figure out what their actual meaning is. Can someone explain what the axes and different colours mean? Also, which is the physical interpretation that can be extracted from them? Thanks in advance :).
  5. patric44

    Question in Bose-Einstein statistics

    iam not getting why in bose statistics the number of ways to arrange ni particles in gi degenerate states is = (gi+ni-1) ? and why do we divide by ni factorial , and gi factorial .
  6. MathematicalPhysicist

    A What is the significance of a 'macroscopic number' in Bose-Einstein condensates?

    In the book A Quantum Approach to Condensed Matter Physics by Taylor and Heinonen they write the following passage on page 87: Now I don't understand what does it mean "macroscopic number", how many particles?
  7. L

    I The deduction of Fermi-Dirac and Bose-Einstein distrbiutions

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  8. S

    B Bose-Einstein Condensate Photons

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  9. Andrew Lewis

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  10. Decimal

    Statistical Mechanics: Cooling to Bose-Einstein condensate

    Hello, I have a question regarding the derivation for Bose Einstein condensation. I understand that in a boson gas for high temperatures the expectation value of the total number of particles should equal something like: $$ \langle N \rangle \sim T * \eta(z)$$ With ## z = exp(\frac {\mu} {k_b...
  11. D

    Deriving Fermi-Dirac Distribution misunderstanding

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  12. B

    B Practical use of Bose-Einstein condensate?

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  13. F

    I Can a particle cause a Bose-Einstein condensate to wave?

    Could a particle move through and displace a Bose-Einstein condensate, causing it to wave?
  14. SlowThinker

    B Pressure of Bose-Einstein condensate

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  15. B

    I Bose-Einstein condensates coherence

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  16. S

    I What are the probabilities for different outcomes with Bose-Einstein statistics?

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  17. L

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  18. T

    I Bose-Einstein distribution for photons

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  19. ShayanJ

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  20. FallenApple

    I Bose-Einstein Condensate Properties

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  21. D

    I A question on Bose enhancement & Pauli blocking

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  22. chikou24i

    A Where Can I Find the Published Paper on Bose-Einstein Statistics by Einstein?

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  23. erbilsilik

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  24. S

    How Can the Gross-Pitaevskii Equation Model BECs at Finite Temperatures?

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  25. C

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  26. fluidistic

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  27. J

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  28. fluidistic

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  29. Davephaelon

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  30. ChrisVer

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  31. D

    Obtain the Fermi function by comparing with the Bose-Einstein function

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  32. M

    Bose-Einstein Stats and Planck Formula

    I worked out the Planck Black-Body Radiation Formula using Bose-Einstein Statistics, but I feel there is something conceptual I am missing here. When Planck derived the formula, he started out with the Boltzmann distribution function, and assumed that there were discrete energy levels...
  33. L

    How can I learn about Bose-Einstein condensate's experimental aspects?

    Hi! Do you tell me where i can found text which discuss about BEC's experimental aspects? Thank you so much.
  34. tom.stoer

    Collapse of a macroscopic Bose-Einstein condensate

    Consider a macroscopic Bose-Einstein condensate. Are there experimental results regarding the propagation (in space and time) of the collapse of this state caused by a point-like perturbation?
  35. F

    Pions vs. Fermi Dirac Statistics and Bose-Einstein Statistics

    Hello! I have a small question, and I am not sure if I am missing something: Today I glanced at the wikipedia page for Pions, and saw this: Statistics: Bosonic Can anyone explain to me why a quark paired with a anti-quark obey Bose-Einstein Statistics? If quarks obey Fermi-Dirac statistics...
  36. JK423

    Bose-Einstein condensation in the canonical ensemble

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  37. G

    Isothermal compressibility of bose-Einstein condensate

    Homework Statement Variables: N (number of particles), μ (chemical potential), P (pression), V (volume). k is Boltzmann's constant. I often use β=1/kT. The (isothermal) compressibility is given by \kappa_{T} = -\frac{1}{V}\left (\frac{\partial V}{\partial P}\right )_{N,T} The...
  38. C

    Quantum entanglement and Bose-Einstein condensation.

    Good afternoon. I am wondering if quantum entanglement could be created between two thermodynamically isolated Bose-Einstein condensates of the same atom produced at the same time in close proximity. Due to the similarity of the systems' mathematics regarding their quantum states (wave...
  39. J

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  40. M

    Calculating the Bose-Einstein Condensation Temperature

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  41. V

    Derivation of ln Z for Bose-Einstein case

    1. Problem From Fitzpatrick we need to deriveln(Z)=αN-\sum ln(1-e^{-\alpha-\betaε_{r}}) (Equation 8.45) Homework Equations This is claimed to be derived from Equations 8.20, 8.30, and 8.43 Eq 8.20 \overline{n}_{s}=-\frac{1}{\beta}\frac{\partial ln(Z)}{\partial\epsilon_{s}} Eq 8.30...
  42. P

    Bose-Einstein condensate of photons

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  43. D

    Ultimate fate of the universe via a Bose-Einstein condensate

    Dear all, I have been reading Wonders of the Universe by Prof. Brian Cox. I enjoyed the TV programs and thought the book would also be interesting, which it is. In the last chapter of the book, and also discussed in the TV program, it talks about the end of the Universe in many trillions of...
  44. J

    How are bosons able to be separated in a Bose-Einstein condensate?

    A question occurred to me concerning the Bose-Einstein condensate: When you have a quantum gas of bosons at a low temperature you obtain a Bose-Einstein condensate where some bosons are in the same state. When you consider the two bosons with the same state, they should behave like one boson...
  45. J

    Bose-Einstein condensate and ions spin

    Is it that correct to say that ions ina B-E condensate rotate at around 10^15 rpm? (don't know the exact english term for this, sorry).
  46. A

    Bose-Einstein Statistics: Finding W.

    Homework Statement Given 4 particles to be divided among 2 zones, one of 3 cells and one of 2 cells. For B-E statistics find W for each macrostate from N1=4, N2=0 to N1=0, N2=4, using both the formula and block diagram. Homework Equations The relevant equation is W=(g+Ni-1)!/(g-1)!Ni...
  47. M

    Mathematica Mathematica, Bose-Einstein

    So, I've managed to get the distribution in a decent way. Using this code; hw = 1; kt = 25; n = 10000; dist[b_] := 1/(b*Exp[hw*m/kt] - 1); normsum[b_] := Sum[dist[b]*(m + 2)*(m + 1)/2, {m, 0, 300}] q = FindRoot[normsum[b] == n, {b, 0.5}] occnumber = Table[N[dist[b /. q]*(m + 2)*(m +...
  48. P

    Is Bose-Einstein Condensation a First-Order Phase Transition?

    I'm not absolutely sure whether condensation of ideal gas of bosons (without any interactions) is a first order phase transition. Some people claim that it isn't first order phase transition because the entropy of a system is continuous function at critical temperature. According to me however...
  49. W

    A little help with Bose-Einstein Condensation

    Hey guys, So I have to make a presentation on this topic. Does anyone of you know of any recent applications of this phenomenon or helpful introductory paper/article? I'm doing my own independent research too but thought that you guys might know of a very helpful resource/idea that I can look...
  50. K

    Unlocking the Power of Supernovas: Exploring Bose-Einstein Condensates

    I was surfing the web and came across where a lab team was messing around with Bose-Einstein Condensate and created what seemed to be a supernova. Here is the link. http://www.space.com/scienceastronomy/generalscience/supernova_lab_010723.html Does anyone on have any idea how this might...
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